Nuts and seeds have a rather low glycemic index because they are relatively low in carbohydrates and higher in fats and protein. Because of this, people who measure foods for the index, often don't bother to measure these foods although I found the glycemic indexes for two types of nuts.
The GI for cashews is 25 and the GI for peanuts is 15. If you have diabetes, nuts and seeds (in moderation due to fat content) are good safe foods, especially if you like to eat them raw. Raw walnuts are best for diabetics because they contain omega-3 fatty acids. Hazelnuts are also good as they contain many beneficial phytochemicals that help to prevent oxidation of fats in the blood stream.
The following article has more information about the health value of nuts for diabetics.http://www.diabetes-guide.org/diabetic-gifts.htm
Here is additional information about the glycemic index (GI). This article explains what the glycemic index is and how to use it:http://www.diabetes-guide.org/glycemic-index.htm
Here is a handy printable PDF file with the GI of common foodshttp://www.diabetes-guide.org/glycemic-list.PDF
This is a list of very low GI foodshttp://www.diabetes-guide.org/low-glycemic-index-foods.htm